CI AI on network chassis

[manisha.singh]

Hi ,

I am using Analog Input and Counter Input simultaneously with a shared internal clock source on the NI cDAQ 9188 chassis with AI ( from NI 9211 ) and CI ( from NI 9402 ). 

I am running NIDAQmx 9.4 on Windows 7 PC.

I get the following error when I start my tasks.

DAQmx Error: An internal error occurred.
Task Name: MyTaskCI
Status Code: -88700

Note that this seems chassis specific. It works fine on my other NI cDAQ 9178 chassis. Please find the code that I am using attached.

Let me know if you need any other information.

Thanks!

Regards,

Manisha Singh

The MathWorks

[Rohama_K]

Hi Manisha,

I ran your code. I got two errors, but they aren't what you got. The first error I got was because the input range for the AI task was incorrect. If you are using NI 9211, the maximum voltage range is  -80 mV to 80 mv. I changed line 67 to this:

DAQmxErrChk (DAQmxCreateAIVoltageChan(taskHandleAI, "cDAQ1Mod1/ai0", "", DAQmx_Val_Diff, -80e-3, +80e-3, DAQmx_Val_Volts, ""));

Another error I was getting was from line 129 and 158. I changed those lines of code to 

printf("EveryNSamplesCallbackCI: totalScansAcquired = %d, scansAcquired = %d\n", totalScansAcquired, scansAcquired);

After I ran your code, I got the attached output screen. By the way, I am using CVI 2010 to run your code. Also using DAQmx 9.4 on a Windows 7 machine.

[manisha.singh]

Hi Rohama,

Thanks for your response. Even after making those changes, it does not work on my network chassis. Did you also run this code on a network chassis? I am using NI cDAQ 9188.

Thanks,

Manisha

The MathWorks

[Rohama_K]

Hi Manisha,

Try simulating your hardware in MAX and then run the code and see if you get the same error message. I have a feeling you won't get it. I'm getting a similar error message when using the cDAQ-9188, NI 9401 and NI 9211.  I am looking into why this internal error is occurring. 

[Rohama_K]

Hi Manisha,

Did you have a chance to simulate your hardware in MAX and try your code?

[Rohama_K]

Hi Manisha,

What OS are you using?

[Corby_B]

Hello Manisha,

Thanks for your post to the DAQ forums!

I have been able to reproduce your issue at our NI R & D center. It is indeed a strange error. I have filed a Correct Action Request on this issue to R & D developers to look into the issue further.

I have been able to reproduce this in LabVIEW as well. One easy work around is to only register for one event. In your case both the AI and CI tasks are synchronized to the same clock rate so you can just read the CI task inside the DAQ event call. Forgive me as I am not as familiar with C so in LabVIEW the solution would look something like this:

You can see that the event is registered for the DAQ task and the CI data is just read inside the event structure at the same time as the AI data. I have tested this on my 9188 and it works very well. Let us know if this helps you get past your issue. My apologies if this has delayed your application. 

Thanks for your time.

Corby

Network cDAQ PSE

National Instruments

[manisha.singh]

Hi corby,

Thanks for your reply. I will try the workaround you mentioned. Can I also get the CAR number for my reference.

Thanks a lot for looking into it.

Regards,
Manisha

[Rohama_K]

The CAR # is 334608. 

[vharihar]

Hello Rohama,

I wanted to follow up with you guys to check if this has been addressed in subsequent versions of the driver. If yes, which version has it been fixed in?

In general, is there an easy way to track if a particular CAR# has been fixed in subsequent versions of the driver?

Thanks,

Varun Hariharan.

The MathWorks.